In this July 12, 2012, photo, a shopper looks at a table of root vegetables for sale at the West Allis Farmers Market in West Allis, Wis. The heat and drought across the upper Midwest have taken a toll on corn and soybeans. (Associated Press)

For those who believe in the scientific method, the last few years have been discouraging. Despite increasingly dire warnings from climate scientists, the public is more concerned about Snookie than a climate that risks our very survival. Republican politicians consider their ignorance and defiance of global warming a badge of honor, while Democrats run and hide if the issue comes up. The rest of the world is waiting for America to lead. My friends and colleagues have despaired that it appears nothing will change until Americans start seeing food shortages. That may become a real possibility, and soon.

Amidst record breaking heat, the worst drought since the 1930s Dust Bowl is choking much of the nation. The National Oceanic and Atmospheric Administration, or NOAA, already ranks this drought as one of the worst on record. Eighty-one percent of the lower 48 states are experiencing at least abnormally dry conditions, and 63 percent are mired in moderate-to-exceptional drought. Parts of 29 states have been declared disaster areas, the largest in our nation's history, much larger than the Dust Bowl area, and long-term forecasts offer no real hope for improvement. Commodity food prices are skyrocketing.

As to the cause, drought experts like Richard Seager, professor at the Earth Observatory at Columbia University, are citing the natural La Nina phenomenon combined with a much warmer climate. Lack of snow last winter expanded the drought. The thin snow cover and early melt across the High Plains not only dried out soils in the MidWest, but likely even affected larger-scale weather patterns. Massive heat waves since March have turbocharged water evaporation from soils and plants, leading to meteorologists calling what we are now suffering a "flash drought," or one that frighteningly accelerates, feeding on itself.

Seager's research revealed that past North American "mega-droughts" have lasted for decades — the Dust Bowl drought lasted 10 years — even without global warming, but they'll be much more likely now. A study found that global warming made the recent Texas, Oklahoma and Mexico drought and heat wave 20 times more likely to occur than 50 years ago. Global warming-induced drying of land mass, planet wide, began in the 1970s, and climate models project a huge expansion of drought areas in the coming decades, depending on how much greenhouse gases continue to be poured into the atmosphere.

Much of the crops in the Midwest, the bread basket of the world, have already burned up this year, and the long-term global warming phenomenon is just getting started. Anyone who eats, or hopes to in the future, should sit up and pay attention. It is long overdue that we behave more cautiously, more conservatively (I can't believe I wrote that) and more like our pioneer ancestors. If given solid evidence that their future was in peril, the Mormon pioneers would surely have already started to prepare for the worst.

Largely overlooked as a means of reducing greenhouse gases, making us less vulnerable to drought and making better use of agricultural land, is how Americans eat. In short, Americans' obsession with meat, beef especially, is unhealthy, a terribly inefficient means of getting enough dietary protein, exacerbates the climate crisis, depletes our soil and threatens our diminishing water resources.

Americans eat about a half a pound of meat a day, twice the average of the rest of the world and far more than required for our protein needs. It takes 6.6 pounds of grain and 1,800 gallons of water to make one pound of beef. It takes 11 times as much fossil fuel and 50 times as much water to make one calorie from animal protein as it does to make one calorie from plant protein.

The livestock industry is responsible for as much global warming emissions as the entire transportation sector. The premier British medical journal, the Lancet, recently published a study demonstrating that if the people in the world's rich nations would merely limit their consumption of meat to the equivalent of one hamburger per day, it would significantly slow the advance of global warming. That seems like a small sacrifice to make for our future, especially compared to the sacrifices our pioneer ancestors made for us in the past.

Dr. Brian Moench is president of Utah Physicians for a Healthy Environment and a member of the Union of Concerned Scientists.